Sage is pretty neat. You open it from the Tools menu in Firefox. It sets up in a sidebar to the left of the screen. You click on a feed, it opens to the actual website in the browser pane to the right that has the focus. All the feeds are stored as bookmarks in the folder of your choice, so they’re always right there. You can get different stylesheets for Sage from the Sage wiki.
What’s best, right click on a link in an item in the reader, tell it to open in a new tab, and it does while the reader stays open. If you have your feeds stored in folders, right click on the folder name, choose Open All in Tabs, and all the feeds in that folder will open in tabs in the browser pane. In this case, the actual feeds open up in the tabs, instead of the website opening.
You get the best of both worlds. If you're in a hurry, you can go to the feed. If you're not, you can go to the actual website. Life is good.